The Voynich manuscript is an illustrated codex hand-written in an unknown writing system. The vellum on which it is written has been carbon-dated to the early 15th century (1404–1438), and it may have been composed in Italy during the Renaissance. The manuscript is named after Wilfrid Voynich, a Polish book dealer who purchased it in 1912. Some of the pages are missing, with around 240 remaining. The text is written from left to right, and most of the pages have illustrations or diagrams. Some pages are foldable sheets.
The Voynich manuscript has been studied by many professional and amateur cryptographers, including American and British codebreakers from both World War I and World War II. The manuscript has never been demonstrably deciphered, and the mystery of its meaning and origin has excited the popular imagination, making it the subject of novels and speculation. None of the many hypotheses proposed over the last hundred years has been independently verified. In 1969, the Voynich manuscript was donated by Hans P. Kraus to Yale University's Beinecke Rare Book and Manuscript Library.